The present invention relates to data communication between a plurality of audio/video (AV) devices and, more particularly, to a system having a digital versatile (video) disc (DVD) device and another AV device wherein data is transmitted and/or received therebetween in accordance with two transmission techniques.
A digital versatile (video) disc (DVD) player may reproduce data recorded on a digital video disc (DVD). More specifically, the DVD player may regenerate or reproduce data from a DVD in a driver section, decode the reproduced data in a decoder section, and provide signals corresponding thereto for enabling a picture to be displayed. The data recorded on a DVD may have been compressed according to a predetermined standard, such as that of a Moving Picture Experts Group (MPEG) standard. Further, the MPEG data recorded on a DVD may be a program data stream which represents a set of programs having video information, audio information, and auxiliary data.
FIG. 14 illustrates a DVD player 1 and a DVD 101. As shown therein, the DVD 101 includes so-called navigation data and so-called presentation data, and the DVD player 1 includes a navigation manager 11 and a presentation engine 12. The presentation data may include video data, audio data, and sub-picture data which corresponds to such video and audio data, and the navigation data may include data pertaining to or utilized in the reproduction of the presentation data such as data which specifies the order of reproduction and/or behavior during the regeneration.
In the DVD player 1, the navigation data is read from the DVD 101 and supplied to the navigation manager 11. The navigation manager 11 generates a control signal in accordance with such received navigation data and supplies the same to the presentation engine 12. Additionally, the presentation data is read from the DVD 101 and supplied to the presentation engine 12. The presentation engine 12 regenerates or reproduces the received presentation data in accordance with the control signal from the navigation manager and outputs the same as a display signal.
In addition to the navigation data, the navigation manager 11 may also receive a command signal corresponding to a user operation from an external device (not shown), and may perform processing in accordance with such command signal. As an example, consider the situation wherein a user desires to change the language of reproduced speech from Japanese to English. In such situation, the user may appropriately operate a speech selection key (not shown), whereupon a command signal corresponding to the desired speech change is supplied to the navigation manager 11. In response thereto, the navigation manager 11 may read a stream number corresponding to a sub-ID of English speech from a table which indicates a relationship between stream number and sub-ID in the navigation data, and may output this information to the presentation engine 12. In response thereto, the presentation engine 12 changes the language from Japanese to English and outputs the speech in English.
FIG. 15 illustrates the navigation manager 11. As shown therein, the navigation manager 11 includes a general controller section 21, an entry searching section 22, a navigation controller section 23, and a user interface controller section 24. As also shown in FIG. 15, the navigation data includes general control data, entry search data, us interface control data, and navigation control data.
The general control data read from the disc 101 is supplied to the general controller section 21. Such general control data may include general information pertaining to a stream of data (such as, the type of broadcast system (NTSC, PAL), the type of compression mode, and so forth) and parental information. The general controller section 21 may set a decoder, or a parameter(s) pertaining thereto, in the presentation engine 12 in accordance with the received general control data. For example, the general controller section 21 may determine the compression of the speech data (such as one of MPEG-Audio, Dolby AC-3, and Liner PCM) to be regenerated or reproduced from the general control data.
The entry search data read from the disc 101 is supplied to the entry search section 22. Such entry search data may include so-called program chain information (PGCI) which may indicate a data regeneration sequence(s) and an address table which indicates the position(s) whereat the presentation data is recorded in the disc 101. The entry search section 22 may select the respective PGCI based on the parental information supplied from the general controller section 21 and an address corresponding to the presentation data.
The user interface control data read from the disc 101 is supplied to the user interface controller section 24. Such user interface control data may include data for prohibiting an operation or for directing an operation if permitted by a user depending on the regeneration position. As an example, the user interface controller section 24 may supply a signal corresponding to an operation to an appropriate circuit (not shown) if such operation is permitted by a user.
The navigation control data, which may be PGCI, is supplied to the navigation controller section 23. The navigation controller section 23 may extract information, such as that pertaining to the order and setting of the regeneration, from the received data and may supply such information to the presentation engine 12.
FIG. 16 illustrates the presentation engine 12. As shown therein, such presentation engine includes a demultiplexer (demux) section 31, an audio decoder 32, a video decoder 33, a sub-picture (SP) decoder 34, a highlight decoder 35, and a superimposition circuit 36.
The demux section 31 receives presentation data from the disc 101 and classifies or determines the type of such data as one of audio pack, video pack, and sub-picture pack in accordance with the stream ID written in the packet header of the presentation data. Based upon the type of data, the demux section 31 supplies output data to the appropriate one of the audio decoder 32, the video decoder 33, and the sub-picture decoder 34 so as to be decoded thereat. A decoded signal from the audio decoder 32 is supplied to a digital-to-analog (D/A) converter 41, whereupon such signal is converted into an analog speech or audio signal and outputted therefrom. Decoded signals from the video decoder 33 and the sub-picture decoder 34 may be supplied to the superimposition circuit 36.
The highlight decoder 35 may provide information pertaining to a position to be highlighted and a color to be used therewith in accordance with highlight information supplied from the navigation manager 11. Decoded highlighted picture information from the highlight decoder 35 may be supplied to the superimposition circuit 36.
The superimposition circuit 36 may receive information representative of a video picture from the video decoder 33, a sub-picture or caption picture from the sub-picture decoder 34, and a highlight picture from the highlight decoder 35, and may superimpose the received information. A superimposed picture signal from the superimposition circuit 36 may be supplied to a digital-to-analog (D/A) converter 42, whereupon such signal is converted into an analog picture signal and outputted therefrom.
Therefore, the navigation manager 11 processes the navigation data and the presentation engine 12 processes the presentation data so as to regenerate or reproduce data recorded on a DVD 101. Further, in processing the presentation data, the presentation engine 12 may utilize information (such as setting information) from the navigation manager 11.
The assignee of the present invention has provided a system in which data read from a DVD may be transmitted to a plurality of digital televisions through a digital interface and the data may be regenerated in each digital television. Such system is described in Japanese Patent Application No. Hei 8-238761 and the corresponding U.S. application Ser. No. 08/926,416 filed Sep. 9, 1997 which are hereby incorporated by reference. However, in this system, the presentation data may be processed in conjunction with navigation data on the transmission side, and thereafter the data is transmitted to the receiving side for decoding. As a result, since such processing is performed on the transmission side, the amount of processing performed on the transmission side is relatively large and, as such, may present a problem.